CONDENSED AND POWDERED MILK 



473 



powder into a suitable collecting-space away from the air current 

 and discharging the air, a vapor, separately from the dry 

 powder." 



After operating under the Stauf patent for about a year, it 

 was seen that a great economical advantage would be effected 

 by condensing the liquid milk in a regular vacuum pan previous 

 to spraying it into the air current. This step was patented 

 July 23, 1907. 



The spray process is adaptable to the desiccation of a great 

 variety of milk products. The first tried out, and for a long 

 time the only highly successful one, was skim-milk. Whole 

 milk, although easily dried, spoiled quickly through the devel- 

 opment of rancidity. Much study and patient research was 

 applied to this problem. Step by step the various factors 

 which produce rancidity were determined. With each step 

 there was an improvement in the keeping qualities, until to- 

 day whole milk can be manufactured to keep nicely for from six 

 months to a year. Not only whole milk but all grades 

 of milk up to 18 per cent cream are now successfully dried. 

 The following table gives the composition of several of these 

 dried products. 



It will be noted that powdered cream has a butter-fat content 

 approaching very closely to that of butter itself. 



Not only is the spray process applicable to such products as 

 the above, which differ from each other mainly in their butter- 



